My SL550 would not start the other day.....the starter battery was dead and had to have it jumped. It looks easy to replace - is there anything I specifically need to know to do that or reset anything else in the car?
T

 

Yes.
Disconnect the rear battery first, then remove and replace the front battery.
Hook up the front battery first, then the rear battery.
You will likely need to reset 'normalize' the windows by running them up and down, and holding them at the limits for 5 seconds.
The ESP will also need to be reset by turning the steering wheel lock to lock a couple times with the car running. This sets the steering angle sensor.

Note - check your owners manual about jumping the car. I believe you are not supposed to jump the front battery, only the rear. Jumping the front may cause other ($$$) problems.

Finally - I have seen many say they cannot find the front battery anywhere except the dealer. I'm sure there are similar batteries that will bolt in place, including AMG or lithium, but the answer is not easy to find. Good luck.

 

Hi there and Thank You so much for this information. You just saved me a bunch of money at the dealer. You are form the US are you? I am from British Columbia in Canada and the price of the starter battery alone is $262.00 and a minimum one hours labour.......so Thanks very much. Seems pretty straight forward.
T

 

"Note - check your owners manual about jumping the car. I believe you are not supposed to jump the front battery, only the rear. Jumping the front may cause other ($$$) problems."


Actually, the R230 dual battery document recommends only jump starting the front battery. However, given the sensitive nature of the electrical system, I would only jump start in an absolute emergency.
Here's a link to the source document that answers many questions:
http://www.benzworld.org/forums/atta...battery-system

 

Great document and Thanks again. Question for you - I will normalize the windows and ESP.
Will the ACC, both seats, steering wheel and mirrors, and Tire pressure monitoring normalize automatically?
T

 

Good question, but I have not had to do any reset, except the ESP and windows. I just learn from everyone else, and share that knowledge and/or personal experience. Welcome to our world... sometimes challenging, but fun driving.

 

Yes and Thanks again....seemed to work well. They are fun cars.
T

 

Mercedes benz dealership charged me $185 diagnostics. They said my car had the following:
1. 2 bad batteries $800 (I changed both for $400)
2. Bad purge valve $450 (I changed for $70)
3. Now they say it's the alternator $1800 cost

Anybody knows why I am getting this on my dashboard. I literally drive my car once or twice a month. Just recently added trickle chargers. Need advice before I change alternator.

 

Good for you for the DIY so far. It's the only affordable way to own this car.

If you have a bad alternator or regulator, the batteries will constantly drain once you start driving, and the voltage will drop. Because the car uses an electric pump to run the brakes, it freaks out at low voltage and eventually gives out a red STOP warning. Drive far enough and you will see this, then the car will die shortly after from lack of electrical power.

First start the car and check the voltage at the rear battery. It should be about 14 volts. If under 13, you are likely not charging from the alternator. It could be a bad fuse supplying the alternator, so check that first.

If you need an alternator, get an Autozone lifetime alternator for about $150. Disconnect the rear and front batteries (in this order always!), remove the belt, wiring plug and main electrical outlet, and 2 bolts. Wrestle the alternator in and out. Reverse the order and finish the job.

You will need to turn the steering full right and left to clear the ESP error, and normalize the windows by running them full up and down and holding for 5 seconds at the limits.

The error should then clear and you will be back in business. I've gone trough 2 alternators and a rear battery, so this is common.

Let us know how it works out.

 

I have both batteries need replacement as per MB stealer. Should I buy them at autozone especially the starter since I don't see anyone replaced that yet on this forum. Advice appreciated

 

When replacing the front starter battery, you must first disconnect the rear consumer battery, then install the new front starter battery, then reconnect the rear consumer battery.

https://mbworld.org/forums/sl-class-...r-battery.html

The Consumer battery can be replaced with one from Advance Auto. Part # 48H8 https://shop.advanceautoparts.com/fi...-sl500-battery

The starter battery can be replaced with one from:

Advance Auto : Part # V4 https://shop.advanceautoparts.com/fi...-sl500-battery

Oreilly's. Part# V4EXTJ https://www.oreillyauto.com/shop/b/b...des-benz/sl500

 

I have replaced both of mine with the Advance Auto batteries. As Aussisuede says, always disconnect the rear (consumer) battery first, and reconnect it last. In other words, never disconnect or reconnect the front (starter) while the rear (consumer) battery is connected.

You may lose a few settings. Your radio station presets will keep, but the sound settings won't. You may lose the steering angle sensor calibration. If you get an "ESP Unavailable" message, just turn the steering wheel fully lock-to-lock a few times while in park with the engine running to clear that. Also, the windows may need to be re-synced, and until then, the top may not operate. To resync the windows, lower them, then fully raise each one while holding the switch up fully for an extra 5 seconds. If the windows bounce-back when raised with the top closed, resync them with the top down.

 

 

 

 

 

2013 is an R230 - go here: https://mbworld.org/forums/sl-class-r231-159/

 

 

 

 

 

 

On the R230, there are two batteries: A larger one (size H6) in the trunk, for all of the vehicle's electrical consumers except the starter, and a smaller one (size V4) under the hood just for the starter. This setup was implemented due to the SBC system which uses an electric pump to provide pressure for the brakes. Having the starter battery isolated, it prevents the consumer battery, which powers SBC, from being drained due to cranking.

On the R231, there are also two batteries. The main vehicle battery (size H8) is in the trunk and is used for all vehicle functions, including the starter. There is a very small auxiliary battery (size 14-BS) located in the compartment behind the passenger seat, with the fuse panel. This setup was implemented due to the electronic shifter. Since the shifter on the center console is not mechanically connected to the transmission, the auxiliary battery is used to power it in the even that the main battery is discharged. This would allow the vehicle to be shifted into neutral for towing.

@John Cooper I stated this earlier - if you have a MY2013 or later SL, then you have an R231, not an R230. This forum is for the R230. You should be looking in the R231 forum for assistance.

In fact, here is a recent thread there about your car's batteries:

https://mbworld.org/forums/sl-class-...ent-guide.html

 

 

Can I ask from where you obtained this information?

My starting problem symptoms seem to imply this is true, but in my thread about my re-starting issues, it has been soundly denied that this can occur.